Conjunctival Biopsy Site in Mucous Membrane Pemphigoid

Area of Science:

• Ophthalmology
• Immunology
• Dermatology

Background:

• Mucous membrane pemphigoid (MMP) is a rare, chronic autoimmune blistering disease.
• Ocular involvement is common and can lead to severe vision impairment.
• Accurate diagnosis of ocular MMP relies on direct immunofluorescence (DIF) testing of conjunctival biopsies.

Purpose of the Study:

• To determine if the conjunctival biopsy site (lesional, perilesional, or nonaffected) impacts direct immunofluorescence (DIF) test results in suspected ocular mucous membrane pemphigoid (MMP).

Main Methods:

• A retrospective case series analyzed records of patients with clinically suspected ocular MMP.
• Conjunctival biopsy sites were categorized as lesional, perilesional, or nonaffected.
• DIF positivity was defined by specific immune deposits at the basement membrane.

Main Results:

• Of 32 eligible patients, 56% had biopsies from nonaffected conjunctiva, 22% from lesional, and 22% from perilesional sites.
• Direct immunofluorescence (DIF) positivity rates were 17% for nonaffected, 14% for lesional, and 86% for perilesional biopsies.
• Perilesional biopsies showed a significantly higher positive DIF rate compared to lesional biopsies (P = .029).

Conclusions:

• Sampling perilesional conjunctival tissue is crucial for increasing the diagnostic yield of DIF testing in suspected ocular MMP.
• Perilesional biopsies are associated with a significantly higher rate of positive DIF results.
• These findings underscore the importance of biopsy site selection for accurate MMP diagnosis.